Automotive suspension ball joint checking mechanism and method

ABSTRACT

A hanger suspended by a hook from the upper control arm of an automotive wheel support carries a disengageable lever, the short end of which engages beneath the lower control arm. Downward swinging of the long arm of the lever will contract the tongs formed by the hook and short lever arm engaged with the upper and lower control arms and straddling the compression spring engaged between them. The fulcrum pin of the lever is engageable selectively with any set of socket notches in furcations of the hanger for application to differently spaced control arms. Contraction of the tongs compresses the spring between the control arms to relieve the ball joints between the spindle support and the control arms from load so that the amount of backlash between the spindle support and the control arms can be checked.

United States Patent Bohannon et al.

AUTOMOTIVE SUSPENSION BALL JOINT CHECKING METHOD Inventors: James P. Bohannon, Salinas, Calif.;

Loyd O. McAfee, Seattle, Wash.

Related US. Application Data Division of Ser. No. 768,418, Oct. 17, 1968, Pat. No. 3,612,485.

.u.s. Cl ..2s1/1 1m. Cl. .3661 3/00 Field of Search .....254/10.5; 33/203.18; 29/401; 33/143 References Cited UNITED STATES PATENTS 3/1966 Cermenaro ..254/l3l [111 [451 March 6, 1973 3,487,551 1/1970 Eggert ..33/203.l

Primary Examiner-Othell M. Simpson Assistant Examiner-Robert C. Watson Attorney-Robert W. Beach 5 7 ABSTRACT A hanger suspended by a hook from the upper control arm of an automotive wheel support carries a disengageable lever, the short end of which engages beneath the lower control arm. Downward swinging of the long arm of the lever will contract the tongs formed by the hook and short lever arm engaged with the upper and lower control arms and straddling the compression spring engaged between them. The fulcrum pin of the lever is engageable selectively with any set of socket notches in furcations of the hanger for application to differently spaced control arms. Contraction of the tongs compresses the spring between the control arms to relieve the ball joints between the spindle support and the control arms from load so that the amount of backlash between the spindle support and the control arms can be checked.

1 Claim, 7 Drawing Figures AUTOMOTIVE SUSPENSION BALL JOINT CHECKING MECHANISM AND METHOD This application is a division of application Ser. No. 768,418, filed Oct. 17, 1968, now US. Pat. No. 3,612,485, for Automotive Suspension Ball Joint Checking Tongs.

It is the principal object of the invention to provide mechanism including an automotive suspension, par ticularly for a front wheel and especially one employing a compression spring, for the purpose of checking the tightness or looseness of the ball joints of the suspension without demounting the suspension in any way.

Another object is to provide a method for the purpose of effecting such wheel suspension ball joint checking quickly and easily.

FIG. 1 is a top perspective of checking tongs with components being shown in exploded relationship.

FIG. 2 is a top perspective of an automobile frontwheel suspension showing the checking tongs applied to it.

FIG. 3 is a side elevation of a wheel suspension with tongs in one adjusted position applied to it and FIG. 4 is a similar view with the tongs in a different adjusted position.

FIG. 5 is a top perspective of checking tongs of somewhat modified structure with parts in exploded relationship and parts broken away.

FIG. 6 is a side elevation of a portion of the tongs shown in FIG. 5, and FIG. 7 is a side elevation of the lever component of such tongs, parts of which are broken away.

While the checking tongs for combining with an automotive wheel suspension could be of integral construction, it is preferred that they be composed of two principal components which are demountable, one component being a hanger supportable from the upper control arm of the automotive wheel suspension and spanning the wheel suspension and the other being a lever which can be carried by the hanger and engaged with the lower control arm of such a suspension. In FIG. 1 the hanger component is shown as including a substantially straight elongated hook arm 1 carrying at an acute angle to it a bifurcated upright having parallel furcations 2. The lower ends of such furcations may be secured together and held in definitely-spaced relationship by a spacer block inserted between and secured to the lower ends of the furcations. The furcations preferably are flat bars disposed with their principal faces parallel. The edges of such bars opposite the hook 1 have in them a plurality of spaced socket notches 3 a which, as shown best in FIGS. 3 and 4, slope upwardly from their bottoms to their open ends.

The lever component 4 includes a long arm at one side of the fulcrum pin 5 and a short arm at the opposite side of such pin. Such short arm is shorter than the hook arm 1 projecting from the upright 2 as shown in FIG. 1 and is formed by a bar of a thickness to be lodged between the furcations 2 of the hanger. The fulcrum pin 5 is of a size to fit snugly in any selected set of the socket notches 3 of the hanger. The upper edge of the short lever arm has in it notches 6 for antislip engagement with the lower control arm of a wheel suspension. To facilitate manipulation of the lever, its long arm preferably is formed of two portions bent at an obtuse angle to each other, the portion nearer the fulcrum 5 being shorter than the portion farther from the fulcrum.

The principal hanger and lever components of the tongs shown in exploded relationship in FIG. 1 are assembled for use by inserting the short arm of the lever 4 endwise through the slot between the furcations 2 in a direction such that such short arm will be disposed generally parallel to the hook I when the components of the tongs are thus assembled. For some applications of the tongs, it may be desirable to change the location of the lever fulcrum in order to enable the tongs to be applied more readily to a particular type of wheel suspension. For this purpose, the fulcrum 5 can be a loose pin which can be shifted to fit into a hole 7 spaced lengthwise of the lever from the position of the fulcrum 5 shown in FIG. 1. Alternatively, the fulcrum 5 can be a fixed pin and a loose pin 8 can be provided for insertion through the aperture 7 to provide a different fulcrum location. If the pin 5 is fixed and the lever is in the form of a flat bar, the end of the longer portion of the lever can be inserted between the furcations 2 from the hook side until the furcations are located between the fixed pin fulcrum 5 and the aperture 7. The loose pin 8 can then be inserted through such aperture and its ends projecting beyond opposite sides of the lever can be cradled in any selected set of the socket notches 3 of the hanger furcations 2.

A typical wheel suspension of the type with which the checking tongs are combined is shown in FIGS. 2, 3 and 4. The upper control arm 9 has connected to it the ball joint 10 which carries the spindle support. Such control arm also has a spring perch which engages the upper end of the helical compression spring 11. The lower end of such spring is engaged with a spring perch on the lower control arm 12. In most cases, such lower control arm has a downwardly projecting strengthening rib extending lengthwise of it. The checking tongs are applied to the outer ends of the upper and lower control arms of such a wheel suspension straddling the spring 11, so that force can be exerted on such arms in opposition to the force of the spring to move such outer control end arms toward each other slightly. Such movement should be sufficient to relieve the upper ball joint 9 and the lower ball joint (not shown) connecting the spindle support to the lower control arm from the stress exerted by the spring.

In combining the checking tongs and the wheel suspension, the hook I of the hanger is hooked over the upper control arm as shown in FIGS. 2, 3 and 4. Such hook is arranged at an acute angle to the hanger upright, so that even though the upright is not precisely vertical, a downward force applied to it will tend to move the upright toward the upper control arm rather than tending to shift the upright away from the upper control arm and slide the hook off such control arm. When the fulcrum pin 5 is engaged in the proper pair of socket notches 3 on the upright to locate the short arm of the lever immediately beneath the lower control arm, one of the lever notches 6 can be engaged-with the rib on the bottom of the lower control arm when the lever is in the broken-line'position of FIG. 3 and the full-line position of FIG. 4. If pressure is then applied manually to the long arm of the lever to swing it from the broken-line position to the solid-line position of FIG. 3, the tongs jaws formed by the hook I and the short arm of the lever will contract the upper and lower control arms of the wheel suspension so as to relieve the upper and lower ball joints of stress produced by spring 1 l. The amount of backlash of the wheel suspension ball joints can then readily by detected by moving the wheel spindle support.

Since automotive wheel suspensions differ both in height and in width, it is desirable to provide a substantial number of notches in the upright furcations 2 of the hanger in order to enable the lever fulcrum to be positioned at the appropriate elevation relative to hook I over a considerable range. Also, it is desirable both to provide in the short arm of the lever 4 several notches 6 and to provide for at least two different positions of the fulcrum along the length of the lever. FIGS. 2 and 3 show the checking tongs combined with a wheel suspension when the fulcrum S nearer the short end of the lever is engaged in a pair of notches 3 of the furca tions 2. In FIG. 4 an arrangement of the tongs is shown with a wheel suspension which is wider and not as deep in relaxed condition as the wheel suspension of FIGS. 2 and 3. In this instance, the fulcrum pin 8 is engaged with a pair of the socket notches 3 of furcations 2.

The hanger and lever components of the tongs shown in FIGS. 5, 6 and 7 are of somewhat different construction than those of the tongs shown in FIG. 1, but the tongs of these figures can be used in the same manner. In this instance, the hanger again includes the hook I disposed at an acute angle to the bifurcated upright, including-furcations 2', but the-furcations are of cantilever structure having free lower ends. Again, however, these furcations are of flat bar structure disposed with their principal faces in parallel relationship. Their edges opposite the hook have socket notches 3 in them to receive the opposite ends, respectively, of fulcrum pin 5 which project beyond the opposite sides of the lever.

The lever 4 of the tongs shown in FIGS. 5, 6 and 7 includes a flat bar portion carrying fixed fulcrum pins or dowels 5 and 8', respectively, which are spaced lengthwise of thelever. The short arm of the lever has upwardly opening notches 6 engageable with the lower control arm of a wheel suspension. Again, the long arm of the lever includes two portions disposed at an obtuse angle to each other. The portion at the side of such angle adjacent to the fulcrum 8' is of flat bar structure. In this instance, however, the structure-of the long arm portion at the side of the long arm bend remote from the fulcrum is of a construction different from the corresponding portion of the lever shown in FIG. 1.

The long arm of the lever 4 is composed of two portions. One portion is tubular and the other portion has a threaded stub 13 which can be inserted into the adjacent end of the tubular lever arm portion. Such'tubular arm portion end has an internal thread 14 which can be screwed onto the stub 13. This threaded connection may be screwed sufficiently tightly to form a perits end having threads 14 can also be threaded to receive a threaded plug 15.

In FIGS. 6 and 7 one end of the tubular lever portion 4' is fitted over an unthreaded stub 16 of the other lever portion. Such tubular I portion and stub can. be secured together by pins. Suc pins can be removable if it is desired to make the two parts of the lever demountable. Otherwise, such pins can be in the form of rivets to provide a permanent joint. Alternatively or additionally, the two parts of the lever can be welded together, as indicated in FIG. 7, if a permanent joint is desired.

The checking tongs shown in FIGS. 5, 6 and 7 can be used for checking ball joint backlash in an automotive wheel suspension in the manner described with reference to FIGS. 2, 3 and 4. In this instance, however, the short end of the lever 4 can be'inserted between the furcations 2 of the hanger by movement longitudinally of the hanger upright between the free ends of the furcations, instead of the short end of the lever being inserted in the direction indicated by the arrow in FIG. 5 generally lengthwise of the lever and transversely of the hanger upright. Such capability is particularly important when it is desired to engage the fulcrum pin 8 with a pair of socket notches 3. In such case the flat bar portion of the lever between fulcrums 5 and 8' can be inserted between the furcations 2 by movement lengthwise of such furcations. The fulcrum pin 8' can then be engaged with a desired pair of socket notches by lengthwise movement of the lever 4 toward the hanger upright from the relationship of'the components shown in FIG. 6.

We claim:

1. The method of enabling backlash to be detected in a ball joint of an automotive wheel suspension having an upper control arm, a lower control arm, a spindle support engaged between the upper control arm and the lower control arm, a ball joint engaged between one of the control arms and the spindle support and spring means pressing one of the control arms, which method comprises, while the ball joint remains in its assembled relationship in the automotive wheel suspension, engaging the upper control arm, engaging the lower control arm, and exerting pressure on the engaged portions of the upper control arm and of the lower control arm to reduce the force on the ball joint for enabling looseness in the ball joint to be detected. 

1. The method of enabling backlash to be detected in a ball joint of an automotive wheel suspension having an upper control arm, a lower control arm, a spindle support engaged between the upper control arm and the lower control arm, a ball joint engaged between one of the control arms and the spindle support and spring means pressing one of the control arms, which method comprises, while the ball joint remains in its assembled relationship in the automotive wheel suspension, engaging the upper control arm, engaging the lower control arm, and exerting pressure on the engaged portions of the upper control arm and of the lower control arm to reduce the force on the ball joint for enabling looseness in the ball joint to be detected. 